osCommerce application

Hello, I'm trying to get a quote on an osCommerce customization. I like to make it look like the website of best buy ([login to view URL]) and being able to let users log on and after that being able to see prices, otherwise it would be like an online catalog, only registered users should be able to view prices and ask for a product or quote. One of the main challenges is that this customers has a point-of-sale application based on MS-DOS and it's quite dificult for me to offer any automation of inventory through this website, since the application will be hosted at my server and the POS applicatin resides in a server inside its facilities. One point would be to make a tool inside osCommerce that allows for importing od DBF files or CSV format files into osCommerce, (he carries about 900 products in stock and around 2000 product catalog) and thus being able to update the prices and specifications of the products. Since it's a retail brick and mortar business it's quite hard to tie both ventures into one, so I guees our best bet is to import the files from the DOS based application and have a delay of about 24 hours. The prospect wants to have as much control over the inventory, I mean since its DOS application manages and controls inventory he wants to have no discrepancies between the web aplication and its P.O.S. application, or as little as possible so as not to sell something he doesn't have in stock. Other than that (which I think is the most difficult part of the project) everything just have to look like best buy's website.